Filter assemblies for drains and having overflow capabilities are known in the prior art. For example, U.S. Pat. No. 438,465 issued Oct. 14, 1890 to Blessing discloses an overflow device for use in bathtubs or set basins. The device includes a tubular shaft having a pair of bands of openings having equal dimensions. The openings permit water to flow therethrough but prohibit the flow of solid articles, such as washcloths, therethrough. Should the openings in the base of the assembly become clogged, the water will rise high enough in the basin or tub to reach the overflow openings at the top of the assembly. The water then flows through the overflow openings to permit draining of the sink or tub.
U.S Pat. No. 3,330,417 to Gold et al issued July 11, 1967 discloses another type of overflow drain device. The Gold et al patent provides a tubular member having an opening at the top thereof. The opening permits water to flow therethrough. This opening provides a swirl pattern in the sink to transport floating refuse and prevents stagnation of the water flow. The floating refuse is trapped inside the assembly and not permitted to flow into the drain.
Prior art structures are deficient in that once the holes become plugged, they must be manually cleaned in order to permit water to flow therethrough.